In general, the quality of chocolate is greatly influenced by the raw materials used and various production conditions and, in particular, sufficient care should be taken not to form fat blooming which stains the surface of a product in off-white during its storage, resulting in loss of commercial value of the product.
A laurin fat, the main constituent fatty acid of which is lauric acid having 12 carbon atoms, has been known to be a raw material fat for the production of chocolate which does not require a tempering operation and, in addition to the production of bar chocolate, it has been used for the production of chocolate for coating cakes, doughnuts, biscuits and the like by blending suitable other oils and fats. However, the problem of fat blooming is still present.
Heretofore, various studies have been made to prevent or control fat blooming of chocolate using laurin fats (hereinafter sometimes referred to as "laruin fat chocolate"). Such studies include improvement of production processes of chocolate, modification of fats to be used, addition of surfactants as anti-blooming agents and the like.
As examples of addition of surfactants, JP-A 61-67444 discloses addition of a sorbitan saturated fatty acid ester together with a glycerin saturated fatty acid ester to a fat ingredient of chocolate. JP-A 64-39945 and JP-A 2-35042 disclose the addition of certain sugar fatty acid esters.
These conventional methods give certain improvements in the production of bar chocolate. However, for the production of covering chocolate, they are still insufficient. In addition, there is another problem that the use of sorbitan saturated fatty acid esters and sugar fatty acid esters debases the flavor of chocolate.